A large-caliber high-speed valve for launch boost and its water entry test device

Abstract

The present invention provides a large-caliber high-speed valve for launch boost and its corresponding water entry test device and design method, belonging to the technical field of high-speed water entry test. The high-speed valve includes a sealing plate, which is tightly fitted with a water target window through an explosive bolt, a launch device and a sealing plate are connected through a push rod, and the launch device is located outside the water target; the launch device and the explosive bolt are respectively connected to a controller; the launch device includes a launch base for installing a gun barrel, an electric firing mechanism is arranged at the closed end of the gun barrel, and the electric firing mechanism is connected to the controller; a push rod is embedded at the open end of the gun barrel; propellant is embedded between the push rod and the closed end of the gun barrel, and the electric firing mechanism is used to fire the propellant and push the push rod to move. The high-speed valve effectively solves the problem of providing an equivalent horizontal liquid surface under non-horizontal conditions in engineering practice, and creates good test conditions for large-scale ground tests of high-speed water entry in the horizontal direction.

Description

Technical Field

[0001] The invention relates to the technical field of high-speed water entry tests, and in particular to a large-caliber high-speed valve for launch boosting and a corresponding water entry test device. Background Art

[0002] High-speed water entry is an important research topic in the fields of air-dropped torpedoes, supercavitating projectiles, and water landing of spacecraft. The process has the characteristics of strong transient, unsteady and high load. Limited by the test funds, it is often necessary to conduct ground tests of horizontal water entry to be equivalent to real water entry flight tests. Therefore, it is of great significance to carry out research on equivalent water target tests to provide a test environment equivalent to the horizontal liquid surface for high-speed water entry test devices.

[0003] At present, a water entry window is usually provided by sealing the entrance with a plastic film or plexiglass. However, a large water target window needs to be sealed with a reinforced and thickened plastic film or plexiglass. The reinforced and thickened plastic film or plexiglass has high strength and toughness, which will cause a large impact load on the high-speed water entry test device, thereby seriously affecting the equivalence of the ground test and the actual water entry test. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a large-caliber high-speed valve for launch boosting, comprising a sealing sheet, an explosive bolt, and a launch device; the explosive bolt is used to fix the sealing sheet to the outer surface of the window of the water target to close the window;

[0005] The launching device comprises a launching base, a gun barrel, an electric firing mechanism, a push rod and propellant, wherein the launching base is fixedly installed relative to the water target; the gun barrel is fixedly connected to the launching base, one end of which is a closed end and the other end is an open end; the electric firing mechanism is arranged at the closed end of the gun barrel; one end of the push rod is embedded in the gun barrel from the open end of the gun barrel, and the other end is fixedly connected to the sealing sheet, and the propellant is embedded between the push rod and the closed end of the gun barrel;

[0006] The explosive bolt and the electric firing mechanism are respectively connected to an external controller. When receiving a control signal from the controller, the explosive bolt is disconnected, and at the same time, the electric firing mechanism fires the propellant to shoot the push rod at a predetermined speed, thereby driving the sealing sheet to be removed from the front of the window.

[0007] A fixed base is arranged outside the sealing sheet, and the other end of the push rod is fixedly connected to the fixed base.

[0008] The launching device is provided with one or two push rods.

[0009] The fixed base comprises a front fixed base and a rear fixed base, wherein the front fixed base is arranged on one end of the sealing sheet close to the emission base, and the rear fixed base is arranged on one end of the sealing sheet far away from the emission base.

[0010] The angle between the gun barrel and the side wall of the water target can be dynamically adjusted between -5° and 10°; in one embodiment, the angle between the gun barrel and the side wall of the water target is between -1° and 1°.

[0011] When the high-speed valve is working, the controller calculates the time when the test device enters the water and the appropriate time to release the seal, and delays. After the preset time is reached, a command to open the valve is issued, and the explosive bolt is immediately detonated. After the explosive bolt is detonated, the connection with the outer wall of the water target and the sealing plate is cut off within a time not exceeding 1ms; the controller delays according to the disconnection time parameter of the explosive bolt, and after the preset time is reached, an ignition command of the electric firing mechanism is issued, and the electric firing mechanism ignites the electric primer, so that the propellant ignites and pushes the push rod, so that the push rod obtains a specified initial velocity and breaks away from contact with the liquid surface at a high speed.

[0012] The high-speed valve provided by the present invention has a response time of less than 1 millisecond and a short dynamic response time.

[0013] On the other hand, the present invention also provides a high-speed water entry test device, which includes a simulation device, a speed measuring target, a water target and a controller. The water target is a water target filled with water and is arranged in front of the flight direction of the simulation device. The outer wall of the water target includes a window on the side close to the simulation device. The window is closed by the large-caliber high-speed valve described in the first aspect of the present invention. When the high-speed valve is fully opened, a flat liquid surface without support can be maintained at the window.

[0014] The controller controls the large-diameter high-speed valve so that: the time t from the end of the speed measurement target measuring the speed of the simulation device to the time when the controller sends a control signal to open the large-diameter high-speed valve Delay for;

[0015]

[0016] Among them, t Estimate Indicates estimated time,

[0017]

[0018] t Hit It represents the time from the end of speed measurement to the impact on the water target, t Overflow It means the time from when the controller sends out the valve opening signal to when the liquid leaves the side wall of the water target and reaches the maximum distance h Overflow The time required; t Open Indicates the time from when the controller sends a signal to open the valve to when the valve is fully opened.

[0019] The time period from when the valve is fully opened to when the water overflows covers the estimated time interval for the simulation device to hit the water target:

[0020]

[0021] Δt Hit Represents the time estimation error of hitting the water target caused by velocity measurement error.

[0022] The working process of the high-speed water entry test device includes the following contents:

[0023] 1) Calculate the amount of propellant: Load the propellant and the electric firing mechanism into the barrel. The amount of propellant is calculated based on the time it takes for the valve to fully open (recommended not to exceed 20ms) and the total mass of the valve.

[0024] 2) Determine the number of push rods: If the area that the valve needs to seal is small, that is, the valve mass is small and a single barrel can be loaded with a large amount of propellant, a single push rod is used to ensure high reliability of the system; if the area that the valve needs to seal is large, that is, the valve mass is large and a single barrel can be loaded with a small amount of propellant, a multi-push rod form is used to ensure that the system can quickly push the valve open with a large thrust.

[0025] 3) Determine the main parameters of the sealing piece: the push rod matches the internal size of the barrel; strength requirements, the sealing structure cannot disintegrate during the propellant boost stage; quality requirements, in order to improve the response speed of the system, the sealing structure should be as light as possible; sealing requirements, in order to prevent liquid leakage, the sealing structure must be able to fit well with the outer wall of the water target window, and the explosive bolts can better fix the sealing structure.

[0026] 4) Determine the installation position of the high-speed valve: there must be no obstacles in the flight direction of the sealing piece.

[0027] Preferably, the sealing sheet flies in a horizontal direction. If the sealing sheet flies in a vertical direction, the sealing structure may fall back into the water target window.

[0028] 5) Determine the main parameters of the explosive bolt: The explosive bolt should be cut off from the outer wall of the water target and separated from the sealing plate within 1ms after the controller issues the detonation command to ensure that the subsequent push rod can push the sealing plate smoothly and quickly.

[0029] After the controller issues a command to open the valve, all explosive bolts should be detonated simultaneously to ensure that the connection between the explosive bolts, the sealing plate and the water target is quickly and synchronously cut off.

[0030] There is no obstruction behind the explosive bolt along the push rod direction to ensure that even if the explosive bolt fails to work, the launching device can still use a strong thrust to forcibly cut off the connection between the sealing structure and the water target window.

[0031] At the moment when the sealing sheet of the water target side wall is separated from the water target, the free liquid surface in the water target can be kept flat, and the flatness time is t Flat :

[0032] t Flat =t Overflow -t Open (1)

[0033] Among them, t Open Indicates the response time of a high-speed valve, that is, the time from when the controller sends a signal to open the valve to when the valve is fully opened (the push rod flies away from the side edge of the water target window);

[0034] t Overflow Indicates the overflow time of the liquid, that is, the maximum distance from the controller sending the valve opening signal to the liquid leaving the water target side device is h Overflow The time required; in h Overflow Under certain circumstances, t Overflow It is a fixed value.

[0035] t Flat It indicates the time for the liquid surface to remain flat without support, that is, the time required from the push rod flying away from the side edge of the water target window to the liquid overflowing.

[0036] The function of the high-speed valve is to provide a free-standing flat (or non-overflowing) liquid surface at the opening covered by the high-speed valve on the side wall of the water target at the moment when the valve is fully opened. Therefore, the parameters that the high-speed valve needs to meet are: t Flat >0(or t Overflow >t Open ), otherwise the valve may not be fully opened and the liquid level may rise (or overflow in large quantities).

[0037] t Flat The larger the value, the longer the liquid surface can remain flat without support, and the better the performance of the high-speed valve.

[0038] t Open Related to the performance of high-speed valves, t Open The smaller it is, the higher the acceleration performance of the launching device. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Schematic diagram of the composition of a high-speed water entry dynamic response test device in an embodiment of the present invention;

[0040] Figure 2 is a schematic structural diagram of a high-speed valve in the form of a single push rod in an embodiment of the present invention;

[0041] Figure 3is a schematic diagram of the structure of a high-speed valve in the form of multiple push rods in an embodiment of the present invention;

[0042] Figure 4 It is a test timing diagram in an embodiment of the present invention.

[0043] Figure 1 - Figure 3 middle:

[0044] 1-explosive bolt; 2-sealing piece; 3-push rod; 4-barrel; 5-propellant; 6-electric firing mechanism;

[0045] 11-simulation device; 12-rocket sled; 13-rocket sled track; 14-speed target; 15-high-speed valve. DETAILED DESCRIPTION

[0046] The specific implementation modes of the present invention are described in detail below with reference to the accompanying drawings.

[0047] Figure 1 Schematic diagram of the high-speed water entry dynamic response test device in an embodiment of the present invention. Figure 1 As shown, a high-speed water entry test device includes a simulation device 11, a speed measuring target 14, a water target and a controller. The water target is a water target filled with water and is arranged in front of the flight direction of the simulation device. The outer wall of the water target near the side of the simulation device includes a window, and the window is closed by a large-caliber high-speed valve 15. The high-speed valve 15 is connected to the controller. When the high-speed valve 15 is fully opened, a flat liquid surface without support can be maintained at the window.

[0048] like Figure 1 As shown, the simulation device 11 is arranged above the rocket sled 12, a rocket sled track 13 is arranged below the rocket sled 12, and the speed measuring target 14 is arranged behind the separation point between the simulation device 11 and the rocket sled 12; a water target filled with water is arranged in front of the flight direction of the simulation device 11 to simulate the water body of the water entry test.

[0049] The simulation device 11 enters the water horizontally, with a flight test equivalent to a real water entry. The key component used at this time is the high-speed valve 15 on the outside of the water target. The high-speed valve 15 needs to meet the conditions such as being able to truly simulate the working conditions of the simulation device 11 entering the water horizontally.

[0050] The high-speed water entry simulation device provided in this embodiment also meets the following conditions:

[0051] The rocket sled 12 is launched from the rocket sled track 13 to provide a specified initial velocity for the simulation device 11. The velocity target 14 measures the flight velocity v of the simulation device 11. E ; The time from the end of the speed measurement to the impact on the water target is t Hit for;

[0052]

[0053] Where, L represents the distance from the end point of the speed measurement to the target, v E It indicates the speed of the simulation device 11 measured at the end point of the speed measurement.

[0054] The controller controls the high-speed valve 15 so that the time from the end of the speed measurement of the simulation device 11 by the speed measurement target 14 to the time when the controller sends a control signal to open the high-speed valve 15 is the delay time t Delay for;

[0055]

[0056] in,

[0057] t Estimate Indicates estimated time; t Hit Indicates the time from the end of speed measurement to the impact of the water target by the simulation device; t Overflow It means the time from when the controller sends out the valve opening signal to when the liquid leaves the side wall of the water target and reaches the maximum distance h Overflow The time required; t Open Indicates the time from when the controller sends a signal to open the valve to when the valve is fully opened.

[0058] According to the test sequence, the above parameters meet the following conditions:

[0059] 1) The time of hitting the water target should not be earlier than the valve opening time and not later than the water overflow time, that is:

[0060] t Delay +t Open ≤t Hit ≤t Delay +t Overflow

[0061] 2) The valve is fully opened earlier than the water overflows, that is:

[0062] t Overflow >t Open

[0063] 3) The time estimation error of hitting the water target caused by the velocity measurement error is Δt Hit ,

[0064] The time period from when the high-speed valve 15 is fully opened to when the water overflows covers the estimated time interval for the simulation device 11 to hit the water target, that is:

[0065]

[0066] Among them, ΔtHit represents the time estimation error of hitting the water target caused by the velocity measurement error;

[0067] 4) The delay time of the controller is not less than 0, that is:

[0068] t Delay ≥0

[0069] In summary, we can get:

[0070]

[0071] Target impact time t Hit The larger the target impact time estimation error Δt Hit The larger the value is, the greater the risk that the time period from valve opening to water overflow cannot cover the target impact time estimation interval; the target impact time t Hit The smaller it is, the shorter the response time of the high-speed valve is, and the greater the risk of collision between the simulation device and the high-speed valve is.

[0072] At the moment when the sealing sheet of the water target side wall is separated from the water target, the free liquid surface in the water target can be kept flat, and the flatness is maintained for a time of t Flat :

[0073] t Flat =t Overflow -t Open

[0074] Among them, t Open Indicates the response time of a high-speed valve, that is, the time from when the controller sends a signal to open the valve to when the valve is fully opened (the push rod flies away from the side edge of the water target window);

[0075] t Overflow Indicates the overflow time of the liquid, that is, the maximum distance from the controller sending the valve opening signal to the liquid leaving the water target side device is h Overflow The time required; in h Overflow Under certain circumstances, t Overflow It is a fixed value.

[0076] t Flat It indicates the time for the liquid surface to remain flat without support, that is, the time required from the push rod flying away from the side edge of the water target window to the liquid overflowing.

[0077] The function of the high-speed valve is to provide a free-standing flat (or non-overflowing) liquid surface at the opening covered by the high-speed valve on the side wall of the water target at the moment when the valve is fully opened. Therefore, the parameters that the high-speed valve needs to meet are: t Flat >0(or t Overflow >t Open ), otherwise the valve may not be fully opened and the liquid level may rise (or overflow in large quantities).

[0078] t Flat The larger the value, the longer the liquid surface can remain flat without support, and the better the performance of the high-speed valve.

[0079] t Open Related to the performance of high-speed valves, t Open The smaller it is, the higher the acceleration performance of the launching device.

[0080] like Figure 2-Figure 3 The large-caliber high-speed valve for launch boost provided in this embodiment is shown, including a sealing sheet 2, an explosive bolt 1 and a launch device.

[0081] The explosive bolt 1 is used to fix the sealing sheet 2 to the outer surface of the window of the water target to close the window;

[0082] The launching device comprises a launching base, a gun barrel 4, an electric firing mechanism 6, a push rod 3 and a propellant 5, wherein the launching base is fixedly installed relative to the water target; the gun barrel 4 is fixedly connected to the launching base, one end of which is a closed end and the other end is an open end; the electric firing mechanism 6 is arranged at the closed end of the gun barrel 4; one end of the push rod 3 is embedded in the gun barrel 4 from the open end of the gun barrel 4, and the other end is fixedly connected to the sealing sheet 2, and the propellant 5 is embedded between the push rod 3 and the closed end of the gun barrel 4;

[0083] The explosive bolt 1 and the electric firing mechanism 6 are respectively connected to an external controller. When receiving a control signal from the controller, the explosive bolt 1 is disconnected, and at the same time, the electric firing mechanism 6 fires the propellant 5 to eject the push rod 3 at a predetermined speed, thereby driving the sealing sheet 2 to be removed from the front of the window.

[0084] Figure 2 The high-speed valve shown comprises a push rod 3, Figure 3 The high-speed valve shown comprises two push rods 3. A fixed base is arranged outside the sealing sheet 2, and the other end of the push rod 3 is fixedly connected to the fixed base. One end of the push rod 3 is embedded in the open end of the gun barrel 4.

[0085] Furthermore, the other end of the push rod 3 passes through the through hole of the fixed base on the outer surface of the sealing sheet 2, and the push rod 3 is connected to the fixed base through the through hole. When the push rod 3 moves, the fixed base moves with the push rod 3, thereby separating the sealing sheet 2 from the water target.

[0086] When the push rod 3 moves, no relative movement occurs between the push rod 3 and the fixed base.

[0087] The gun barrel 4 and the push rod 3 are in transitional fit.

[0088] The fixed base includes a front fixed base and a rear fixed base. The front fixed base is arranged on one end of the sealing sheet 2 close to the emission base, and the rear fixed base is arranged on one end of the sealing sheet 2 away from the emission base.

[0089] The length of the front fixed base is half the length of one end of the sealing sheet 2 where it is located, and the length of the rear fixed base is equal to the length of the end of the sealing sheet 2 where it is located.

[0090] In this embodiment, the angle between the gun barrel 4 and the side wall of the water target can be dynamically adjusted within a range of -5° to 10°.

[0091] In this embodiment, it is preferred that the angle between the gun barrel and the side wall of the water target ranges from -1° to 1°.

[0092] The working process of the high-speed valve is as follows: after the high-speed valve receives the "open valve" signal, the explosive bolt detonates immediately to cut off the connection between the sealing structure and the water target; after the explosive bolt detonates, after a very short delay (the delay time is determined according to the response time of the explosive bolt, generally not exceeding 1ms), the electric firing mechanism in the launching device ignites the electric primer, so that the propellant ignites and pushes the push rod, so that the sealing sheet is separated from the water target window at high speed along the push rod under the action of the push rod.

[0093] The following reference Figure 4 , the test process of the above test device is described in detail,

[0094] The test process of the high-speed water entry test device in this embodiment includes:

[0095] Step 1: The rocket sled 12 is accelerated on the rocket sled track 13 by the rocket thrust, providing a specified initial velocity for the simulation device 11. A velocity target 14 is set behind the separation point between the simulation device 11 and the rocket sled 12, and the flight velocity v of the simulation device 11 is measured by the velocity target 14. E ;

[0096] Step 2: Calculate the target impact time t of the simulation device 11 Hit The estimated error of the time of impact is Δt Hit :

[0097]

[0098] In the formula, Δv E Indicates the speed measurement error of the simulation device.

[0099] Step 3: Calculate the delay time, and send an "open valve" signal to the high-speed valve 15 when the delay time arrives;

[0100] Step 4: After the high-speed valve 15 receives the "open valve" signal, the explosive bolt 1 detonates, and then the sealing piece 2 is pushed away from the window of the water target at high speed by the propellant, and then the simulation device 11 collides with the liquid surface before the water overflows, and the dynamic response data of the simulation device 11 is obtained.

[0101] Without the high-speed valve 15 blocking, the liquid in the water target window will experience a process of accelerating from 0 to a steady-state speed, and the liquid acceleration a Fluent ≤g (gravitational acceleration), considering that the liquid has already overflowed when it reaches the steady-state speed, the liquid loses the valve shielding and undergoes a short acceleration time t Flow = After 100ms, the vertical distance h from the liquid surface to the side wall of the water target Flow satisfy:

[0102]

[0103] In this embodiment, the standard for setting the liquid surface to be flat is:

[0104] h Flow ≤h Overflow =50mm

[0105] The liquid surface in the water target can remain flat for at least 100ms after the high-speed valve is opened.

[0106] In this embodiment, the total length of the sealing sheet in the flight direction is L Seal =3m, the ejector's muzzle velocity is v Seal =1000m / s, the movement process of the push rod in the barrel is a uniform acceleration process, and the time required for the sealing piece to fly away from the water target window is:

[0107]

[0108] That is, the valve opening time is earlier than the water overflow time, and after the high-speed valve is opened, the water overflow time is far from being reached, and the liquid surface still has excellent flatness.

[0109] In this embodiment, the distance from the velocity measuring target 14 to the water target is L=10m, and the flight speed of the simulation device 11 is v E =500m / s, the speed measurement error of the speed measurement target 14 is Δv E =5m / s, and then the time t from the end of the speed measurement to the collision of the target by the simulation device 11 is obtained Hit and the estimated error Δt Hit They are:

[0110]

[0111] It can be calculated that the delay time of the controller is t Delay =0ms.

[0112] The above implementation modes are only used to illustrate the technical solutions of the embodiments of the present invention and are not intended to limit the present invention. Although the embodiments of the present invention are described in detail with reference to the above preferred implementation modes, those skilled in the art should understand that the technical solutions of the embodiments of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A large-caliber high-speed valve for launch boost, characterized in that: The high-speed valve comprises a sealing piece, an explosive bolt and a launching device; wherein: The explosive bolt is used to fix the sealing sheet to the outer surface of the window of the water target to close the window; The launching device comprises a launching base, a gun barrel, an electric firing mechanism, a push rod and propellant, wherein the launching base is fixedly installed relative to the water target; the gun barrel is fixedly connected to the launching base, one end of which is a closed end and the other end is an open end; the electric firing mechanism is arranged at the closed end of the gun barrel; one end of the push rod is embedded in the gun barrel from the open end of the gun barrel, and the other end is fixedly connected to the sealing sheet, and the propellant is embedded between the push rod and the closed end of the gun barrel; The explosive bolt and the electric firing mechanism are respectively connected to an external controller. When receiving a control signal from the controller, the explosive bolt is disconnected, and at the same time, the electric firing mechanism fires the propellant to eject the push rod at a predetermined speed, thereby driving the sealing sheet to be removed from the front of the window; a fixed base is provided on the outer side of the sealing sheet, and the other end of the push rod is fixedly connected to the fixed base; One end of the push rod is embedded in the open end of the gun barrel, and the other end of the push rod passes through the through hole of the fixed base on the outer surface of the sealing plate. The push rod is connected to the fixed base through the through hole. When the push rod moves, the fixed base moves with the push rod, so that the sealing plate is separated from the water target. When the push rod moves, there is no relative movement between the push rod and the fixed base. There is a transition fit between the gun barrel and the push rod. The high-speed valve includes one or two push rods. The fixed base includes a front fixed base and a rear fixed base, the front fixed base is arranged on one end of the sealing sheet close to the launch base, and the rear fixed base is arranged on one end of the sealing sheet away from the launch base; the length of the front fixed base is half of the length of one end of the sealing sheet where it is located, and the length of the rear fixed base is equal to the length of the end of the sealing sheet where it is located; The angle between the gun barrel and the side wall of the water target is in the range of -5° to 10°; the angle between the gun barrel and the side wall of the water target is in the range of -1° to 1°; When the high-speed valve is in working state, upon receiving the valve opening signal, the explosive bolt detonates immediately to cut off the connection between the sealing piece and the water target; after a certain time delay after the explosive bolt detonates, the electric firing mechanism in the launching device ignites the electric primer, causing the propellant to ignite and push the push rod, and the sealing piece is separated from the water target window along the push rod under the action of the push rod.

2. A high-speed water entry test device, characterized in that: The test device comprises a simulation device, a speed measuring target, a water target and a controller, wherein the water target is a container filled with water and is arranged in front of the flight direction of the simulation device, and the outer wall of the water target comprises a window on a side close to the simulation device, and the window is closed by the high-speed valve according to claim 1, and the high-speed valve is connected to the controller, and when the high-speed valve is fully opened, a flat liquid surface without support is maintained at the window; The simulation device is arranged above the rocket sled, a rocket sled track is arranged below the rocket sled, the speed measuring target is arranged behind the separation point between the simulation device and the rocket sled; a water target filled with water is arranged in front of the flight direction of the simulation device; The rocket sled is launched from the rocket sled track to provide an initial speed for the simulation device, and the speed target measures the flight speed v of the simulation device. E ; The time from the end of the speed measurement to the impact on the water target is t Hit for; Where, L represents the distance from the end point of the speed measurement to the target, v E Indicates the speed of the simulation device measured at the end point of the speed measurement; The controller controls the high-speed valve, and the time from the speed target to the simulation device ends to the controller sending a control signal to open the high-speed valve is taken as the delay time t Delay : t Estimate Indicates estimated time; t Hit Indicates the time from the end of speed measurement to the impact of the water target by the simulation device; t Overflow It means the time from when the controller sends out the valve opening signal to when the liquid leaves the side wall of the water target and reaches the maximum distance h Overflow The time required; t Open Indicates the time from when the controller sends a signal to open the valve to when the valve is fully opened; and: The time of hitting the water target is no earlier than the valve opening time and no later than the water overflow time: t Delay +t Open ≤t Hit ≤t Delay +t Overflow The valve fully opens earlier than the water overflows: t Over fl ow >t Open The time period from when the high-speed valve is fully opened to when the water overflows covers the estimated time interval for the simulation device to hit the water target: Among them, Δt Hit represents the time estimation error of hitting the water target caused by the velocity measurement error; The controller delay time is not less than 0: t Delay ≥0 Then we have:

3. The high-speed water entry test device according to claim 2, characterized in that: At the moment when the sealing sheet of the water target side wall is separated from the water target, the free liquid surface in the water target remains flat, and the flatness is maintained for a time t Flat : t Flat =t Overflow -t Open Among them, t Open It indicates the response time of high-speed valve, that is, the time from when the controller sends the valve opening signal to when the valve is fully opened. The valve is fully opened when the push rod flies away from the side edge of the water target window; t Overflow Indicates the overflow time of the liquid, that is, the maximum distance h from the time the controller sends a signal to open the valve to the time the liquid leaves the water target side device Overflow The time required; the parameters that high-speed valves meet are: t Flat >0; or t Overflow >t Open .

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